The present invention relates generally to the art of welding-type power supplies. More specifically, it relates to welding-type power supplies and the communication between various devices in such systems.
Welding power supplies or systems are available for a wide variety of processes, and with a wide variety of sophistication. Welding-type power supply or system, as used herein, includes power supplies or systems that provide welding, cutting or heating power, and may include a controller, switches, etc. Traditionally, a good weld required an experienced welder, not only to properly execute the weld, but to properly select operating parameters (such as output voltage, current, power, pulse width, wire feed speed, etc.).
Now, robots are available that execute the weld. Also, orating parameters may be pre-determined and automatically implemented by a controller in the welding-type power supply. The automation is typically a software program that describes the output waveform, and is executed by a digital processor (microprocessors, DSPS, etc.). The program attempts to implement and improve upon the decisions that had been made by the experienced welder. The various welding-type devices in the weld cell must be able to communicate to effectively carry out the programs. Welding-type device, as used herein, includes welding peripherals, and/or welding-type power supplies and sources of welding-type power.
With the increasing sophistication of welding-type power supplies, and the programs they implement, the need for communication between the various devices in a welding-type power supply increases, and the communications must also become increasingly sophisticated.
Traditionally, the communication between devices in a welding-type system or a weld cell was a dedicated link between two devices, wherein data and/or commands were provided on the direct connection.
Networks, to the extent they have been used, have relied upon messages that contained the instructions, commands, and/or data directly. A part of each message was dedicated to refer to a specific command or parameter. Each new command or parameter for a device required the message to be long enough to provide bits dedicated to that new command. Adding a new device to the network could require many new commands, and the concomitantly longer message.
For example, a 16 bit command might have the first 4 bits identify the node to which the communication is intended. The next four bits might set one parameter, such as the current command, the next four bits relate to the wire feed speed, and the last four bits relate to a voltage command. Adding a parameter, such as a pulse width, could require an additional four bits to be added to the message length. One can readily see how increasingly complex messages quickly become ever longer.
Unfortunately, longer messages can bog a system down, make programming a system unwieldy, and upgrading a system difficult. Conversely, sending less information reduces the flexibility, control, and usefulness of a welding-type power supply,
Also, networks developed solely for welding-type power supplies cannot readily take advantage of commercially available network protocols and hardware by using them in a typical fashion. Having each message firmly defined and assigned an explicit address requires knowledge of the network protocol to make changes. As a system for welding evolves and is improved the network messaging scheme would require cumbersome updating and changing.
Accordingly, a welding-type power supply that provides for efficient and economical communication is desirable. Such a system will preferably be able to transmit complex and varied messages. Also, it will preferably be suitable for using with commercially available hardware or software, to allow easier designing, adding on to, and upgrading.
According to a first aspect of the invention, a welding-type system includes a source of welding-type power operatively connected to a controller. The source of welding-type power includes a power network module with a power multiple level message module, and the controller includes a controller network module with a controller multiple level message module. A network is operatively connected to the network modules, and is capable of sending a plurality of multiple level messages.
According to a second aspect of the invention a method of providing welding-type power, includes connecting a source of welding-type power to a network, and connecting a controller to the source of welding-type power. The controller is-also connected to the network. Multiple level messages are sent between the source of power and the controller.
The network is DEVICENET(trademark) compatible in one embodiment.
A welding peripheral and/or a second source of power has a network module with a multiple level module and is connected to the network in another embodiment.
The multiple level message includes an identifier portion and a data portion, and the data portion can include pointer portion and a value portion in various alternatives.
The controller and sources of power and peripheral have memory connected to the multiple level message modules, and store common message decoding data therein so that they have shared knowledge for decoding the pointer portions and data portions. The common data can be, but need not be, the same in all devices.
According to a third aspect of the invention a method of providing welding-type power includes connecting a source of welding-type power to a network and a controller. The controller is also connected to the network. A first set of message decoding data is stored in the controller, and at least a first subset of the first set of message decoding data is stored in the source of power. Thus, the controller and the first source have shared knowledge for responding to a pointer portion and a data portion of a plurality of messages. The messages may or may not be multiple level messages.
According to a fourth aspect of the invention a welding-type power supply includes a source of welding-type power and a controller operatively connected to the source. A network is connected to the controller and the source. The controller includes memory that has a first set of message decoding data stored therein. The source includes memory that has at least a first subset of the first set of message decoding data stored therein. Thus, the controller and the first source have shared knowledge for responding to a pointer portion and a data portion of a plurality of messages.
According to a fifth aspect of the invention a method of communicating between devices in a weld cell includes connecting a first device to a network and connecting a second device to the network. Multiple level messages are sent between the first and second devices.
According to a sixth aspect of the invention a method of communicating between devices in a weld cell includes connecting a first device to a network and connecting a second device to the network. A first set of message decoding data is stored in the first device and at least a first subset of the first set of message decoding data is stored in the second device. Thus, the first and second devices have shared knowledge for responding to a pointer portion and a data portion of a plurality of messages.
According to a seventh aspect of the invention a system for communicating between devices in a weld cell includes a first device with a first network module and a first multiple level message module. Also, second device has a second network module and a second multiple level message module. A network is operatively connected to them, and is capable of transmitting a plurality of multiple level messages.
According to an eighth aspect of the invention a system for communicating between devices in a welding-type power supply includes a first device, a second device and a network connecting them. The devices have memory with common message decoding data stored therein so that they have shared knowledge for responding to a pointer portion and a data portion of a plurality of messages.
Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description and the appended claims.